content: /*
   * Copyright 2011-2016 David Karnok
   *
   * Licensed under the Apache License, Version 2.0 (the "License");
   * you may not use this file except in compliance with the License.
   * You may obtain a copy of the License at
   *
   *     http://www.apache.org/licenses/LICENSE-2.0
   *
   * Unless required by applicable law or agreed to in writing, software
   * distributed under the License is distributed on an "AS IS" BASIS,
   * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
   * See the License for the specific language governing permissions and
   * limitations under the License.
   */
  
  package ix;
  
  import java.util.Iterator;
  
  final class IxReplaySize<T> extends IxSource<T, T> {
  
      final int maxSize;
  
      Iterator<T> it;
  
      Node<T> head;
  
      Node<T> tail;
  
      int size;
  
      IxReplaySize(Iterable<T> source, int maxSize) {
          super(source);
          this.maxSize = maxSize;
          this.head = this.tail = new Node<T>(null);
      }
  
      @Override
      public Iterator<T> iterator() {
          if (it == null) {
              it = source.iterator();
          }
          return new ReplaySizeIterator<T>(this, head);
      }
  
      boolean moveNext() {
          if (!it.hasNext()) {
              return false;
          }
  
          Node<T> n = new Node<T>(it.next());
          tail.next = n;
          tail = n;
  
          int s = size;
          if (s != maxSize) {
              size = s + 1;
          } else {
              head = head.next;
          }
          return true;
      }
  
      static final class Node<T> {
          final T value;
  
          Node<T> next;
  
          Node(T value) {
              this.value = value;
          }
      }
  
      static final class ReplaySizeIterator<T> extends IxBaseIterator<T> {
          final IxReplaySize<T> parent;
  
          Node<T> node;
  
          ReplaySizeIterator(IxReplaySize<T> parent, Node<T> node) {
              this.parent = parent;
              this.node = node;
          }
  
          @Override
          protected boolean moveNext() {
              Node<T> n = node;
  
              if (n.next == null) {
                  if (!parent.moveNext()) {
                      done = true;
                      return false;
                  }
              }
              n = n.next;
  
              value = n.value;
              hasValue = true;
              node = n;
  
              return true;
          }
      }
  }
  